An elevator car of an elevator system is dragged or hung by a dragging medium such as a steel wire or a steel belt. Especially, when the elevator car stops at a floor position to load/unload passengers or articles, the elevator car is hung by the steel wire or steel belt, so as to relatively stop in a shaft, thus facilitating loading or unloading.
However, the dragging medium such as the steel wire or steel belt is somewhat flexible. A great change in the weight of the elevator car during loading or unloading may easily cause vertical vibration of the elevator car, especially when the steel wire or steel belt is long. The elevator car is stopped unstably with respect to a floor position due to this vibration, thus causing poor passenger experience.